src/main.c

   1 /* Top level entry point of bison,
   2    Copyright 1984, 1986, 1989, 1992, 1995, 2000, 2001
   3    Free Software Foundation, Inc.
   4
   5    This file is part of Bison, the GNU Compiler Compiler.
   6
   7    Bison is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2, or (at your option)
  10    any later version.
  11
  12    Bison is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with Bison; see the file COPYING.  If not, write to
  19    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22
  23 #include "system.h"
  24 #include "getargs.h"
  25 #include "files.h"
  26 #include "complain.h"
  27 #include "derives.h"
  28 #include "output.h"
  29 #include "reader.h"
  30 #include "lalr.h"
  31 #include "reduce.h"
  32 #include "nullable.h"
  33 #include "print.h"
  34 #include "LR0.h"
  35 #include "conflicts.h"
  36 #include "print_graph.h"
  37 #include "muscle_tab.h"
  38 #include "symtab.h"
  39 #include "lex.h"
  40
  41 /* The name this program was run with, for messages.  */
  42 char *program_name;
  43
  44 int
  45 main (int argc, char *argv[])
  46 {
  47   program_name = argv[0];
  48   setlocale (LC_ALL, "");
  49   bindtextdomain (PACKAGE, LOCALEDIR);
  50   textdomain (PACKAGE);
  51
  52   lineno = 0;
  53   getargs (argc, argv);
  54
  55   muscle_init ();
  56
  57   /* Read the input.  Copy some parts of it to FGUARD, FACTION, FTABLE
  58      and FATTRS.  In file reader.c.  The other parts are recorded in
  59      the grammar; see gram.h.  */
  60   reader ();
  61   if (complain_message_count)
  62     exit (1);
  63
  64   /* Find useless nonterminals and productions and reduce the grammar. */
  65   reduce_grammar ();
  66
  67   /* Record other info about the grammar.  In files derives and
  68      nullable.  */
  69   set_derives ();
  70   set_nullable ();
  71
  72   /* Convert to nondeterministic finite state machine.  In file LR0.
  73      See state.h for more info.  */
  74   generate_states ();
  75
  76   /* make it deterministic.  In file lalr.  */
  77   lalr ();
  78
  79   /* Find and record any conflicts: places where one token of
  80      lookahead is not enough to disambiguate the parsing.  In file
  81      conflicts.  Also resolve s/r conflicts based on precedence
  82      declarations.  */
  83   solve_conflicts ();
  84   conflicts_print ();
  85
  86   /* Output file names. */
  87   compute_output_file_names ();
  88
  89   /* Output the detailed report on the grammar.  */
  90   if (verbose_flag)
  91     print_results ();
  92
  93   /* Stop if there were errors, to avoid trashing previous output
  94      files.  */
  95   if (complain_message_count)
  96     exit (1);
  97
  98   /* Output the VCG graph.  */
  99   if (graph_flag)
 100     print_graph ();
 101
 102   /* Output the tables and the parser to ftable.  In file output.  */
 103   output ();
 104
 105   /* Free the symbol table data structure.  */
 106   free_symtab ();
 107
 108   reduce_free ();
 109   free_conflicts ();
 110   free_nullable ();
 111   free_derives ();
 112
 113   /* If using alloca.c, flush the alloca'ed memory for the benefit of
 114      people running Bison as a library in IDEs.  */
 115 #if C_ALLOCA
 116     alloca (0);
 117 #endif
 118
 119   return complain_message_count ? EXIT_FAILURE : EXIT_SUCCESS;
 120 }